import  subprocess
#作用执行windons命令
# '''
# sh-3.2# ls /Users/egon/Desktop |grep txt$
# mysql.txt
# tt.txt
# 事物.txt
# '''
# res1=subprocess.Popen('ls /Users/jieli/Desktop',shell=True,stdout=subprocess.PIPE)
# res=subprocess.Popen('grep txt$',shell=True,stdin=res1.stdout,
#                  stdout=subprocess.PIPE)
 
# print(res.stdout.read().decode('utf-8'))


# #等同于上面,但是上面的优势在于,一个数据流可以和另外一个数据流交互,可以通过爬虫得到结果然后交给grep
# res1=subprocess.Popen('ls /Users/jieli/Desktop |grep txt$',shell=True,stdout=subprocess.PIPE)
# print(res1.stdout.read().decode('utf-8'))
 

# #windows下:
# # dir | findstr 'test*'
# # dir | findstr 'txt$'
# import subprocess
# res1=subprocess.Popen(r'dir C:\Users\Administrator\PycharmProjects\test\函数备课',shell=True,stdout=subprocess.PIPE)
# res=subprocess.Popen('findstr test*',shell=True,stdin=res1.stdout,
#                  stdout=subprocess.PIPE)

# print(res.stdout.read().decode('gbk')) #subprocess使用当前系统默认编码，得到结果为bytes类型，在windows下需要用gbk解码
subprocess.call(['java','-version'])